Which is a better lens? The Tamron AF 18-200mm 3.5-6.3 XR Di II Aspherical [IF] Macro Zoom Lens or the Sigma AF 18-200mm F3.5-6.3 DC Zoom Lens? Which is better, which would you buy, and why? (Assuming you would)
The only thing I can say from persoal knowledge is that Tamron has a 6 year warranty while Sigma has a one year one. Also Tamron offers student and educator discounts on all of its products.
I happen to have bought one of the first Sigma 18-200s sold in Canada. I was leaning towards the Tamron, but the dealer I dealt with had the Sigma's on order, but not the Tamron version. I have no idea how the Tamron performs but my Sigma is an extremely good lens for the price, and I have done some rather careful comparison shots against some of my more expensive lenses and it does very well in head to head comparisons.
